In the Field With PEDv
How nasty is the porcine epidemic diarrhea (PED) virus? Take this example from last winter. A group of 62,000 sows on 16 farms in a 10-mile radius in Missouri all broke with the virus from February 4 to February 14, "despite an excellent track record of external biosecurity," says Pete Thomas, veterinarian for Murphy Brown LLC.
Mortality in pigs less than one week old was virtually 100%.
"That was not my favorite Valentine's Day," Thomas told veterinarians at the annual Swine Disease Conference at Iowa State University today.
Intense cleaning and disease management protocols were introduced immediately, but the virus hung on. The reasons this pod of sow farms was a disease clean-up challenge include:
Large walk-through farrowing rooms.
Recycle flush system, shallow manure pits, pit discharge 3. Large sow farm size of 3,800 to 7,600 sows.
Some farms returned to near normal in six weeks, but others showed no signs of improvement despite elimination efforts. Overall, preweaning mortality was consistently running two times higher than pre-PEDv levels.
Thomas ordered a one-month supply of the Harris 2 vaccine, "with little hope it would work." But an immediate and drastic decrease in preweaning mortality was noted on the five farms getting the vaccine. The decision was made to vaccinate all sows.
The last positive test for PEDv was five weeks after the last vaccinated sow farrowed.
Vaccination certainly was not needed to eliminate the virus in every farm, say Thomas, but "In my experience, prefarrow vaccination can be a valuable tool in chronic infection."